Plasma C-reactive protein levels are associated with mortality in elderly with acute lung injury

The plasma C-reactive protein (CRP) level is considered to be a predictor of severity in both hospital- and community-acquired pneumonias, whereas recent reports have shown that higher CRP levels lead to better outcomes in patients with acute lung injury (ALI). To explain this discrepancy, we evaluated the relationship among plasma CRP levels, etiology, affectors of CRP production, and mortality in patients with ALI.

This was a case-control study of 76 consecutive patients with ALI. The plasma CRP levels had been measured in all of the patients within 1 hour of visiting an emergency department. The associations between the plasma CRP levels and 60-day mortality were analyzed after adjusting for the causes of ALI, disease severity, the patients' age, use of corticosteroids, and presence of hepatic failure.

The CRP levels and patients' ages were strongly related to the mortality (adjusted hazard ratio, 1.005 [P = .007] and 1.059 [P = .011], respectively), whereas the etiology of ALI did not affect the mortality (adjusted hazard ratio, 0.789 [P = .530]) in the Cox proportional hazard models.

The plasma CRP level may be a predictor of mortality in elderly patients with ALI.